The USDA Agricultural Research Service (ARS) is seeking three postdoctoral fellows to investigate Salmonella in poultry. Salmonella is responsible for over 1.3 million food borne infections in the U.S. each year. The goal is to eliminate Salmonella from U.S. poultry and reduce the level of human illness. Fellows will study interventions to help reduce Salmonella in poultry, including predictive modeling, vaccines, or probiotics.

The Agricultural Research Service (ARS) is the U.S. Department of Agriculture's chief scientific in-house research agency with a mission to find solutions to agricultural problems that affect Americans every day from field to table. ARS will deliver cutting-edge, scientific tools and innovative solutions for American farmers, producers, industry, and communities to support the nourishment and well-being of all people; sustain our nation’s agroecosystems and natural resources; and ensure the economic competitiveness and excellence of our agriculture. The vision of the agency is to provide global leadership in agricultural discoveries through scientific excellence.

USDA-ARS-2022-0360   USDA-ARS Postdoctoral Fellowship to Investigate Predatory Bacteria for Use as a Probiotic to Reduce Salmonella in Poultry 

*Applications may be reviewed on a rolling-basis.

ARS Office/Lab and Location : A research opportunity is currently available with the U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), located in Providence, Rhode Island and Athens, Georgia. During Year 1 of the project, the ORISE postdoctoral fellow will acquire technical expertise and pursue project objectives at Providence College in Providence, Rhode Island. After this approximately one-year training period, the fellow will transfer to Russell Research Center in Athens, Georgia for the remainder of the fellowship to pursue subsequent project objectives. Relocation funds will be provided to the fellow to offset the cost of moving.

Research Project : The successful applicant will conduct microbiological research to investigate development of the predatory bacterium Bdellovibrio as a probiotic intervention to control Salmonella during poultry production. This project will involve assay development and in vitro high-throughput screening to identify promising predatory bacteria strains followed by in vivo poultry studies to directly test the ability of these strains to reduce Salmonella at different stages of production. This ORISE fellowship offers a unique opportunity for a postdoctoral scientist to conduct research at both a primarily undergraduate institution and a federal research agency.

Learning Objectives : The fellow will learn how to handle predatory bacteria (Bdellovibrio) and target bacteria, Salmonella. They will also learn how to adapt predation assays into a high throughput, 96-well format to screen large numbers of different Bdellovibrio to find the best predator of Salmonella, and also screen large numbers of Salmonella to determine what strains are susceptible to predation. After one year, the fellow will help transfer this technology to the ARS facility in Athens GA, and they will learn how to do animal challenges in poultry and evaluate the Bdellovibrio as a probiotic to reduce levels of Salmonella in poultry. Additionally, the fellow will have opportunities to mentor undergraduate research assistants at Providence College and graduate research assistants in Athens, GA. This unique program will allow a motivated postdoc to develop unique and powerful laboratory skills and also develop mentoring skills necessary for success in their next career goals. The fellow can also benefit from formal and informal training in bioinformatics, statistics, artificial intelligence, computational biology, etc. through courses available through the USDA.

Mentor : At Providence College, Dr. Laura Williams will serve as primary mentor. At Russell Research Center, Dr. Jonathan Frye (jonathan.frye@usda.gov) will serve as primary mentor. The mentoring team is committed to supporting the ORISE fellow’s professional development. If you have questions about the nature of the research, please contact the mentor.

Anticipated Appointment Start Date : As soon as a qualified candidate is identified.  Start date is flexible and will depend on a variety of factors.

Appointment Length : The appointment will initially be for one year, but may be renewed for two additional years upon recommendation of ARS and is contingent on the availability of funds.

Level of Participation : The appointment is full-time.

Participant Stipend : The participant will receive a monthly stipend commensurate with educational level and experience. The current stipend for this opportunity will be $5,823.17 plus $562.68 for medical, prescriptions, dental and vision each month.

USDA-ARS-2022-0361  USDA-ARS Postdoctoral Fellowship to Investigate Genetic Factors Associated with Transmission of Salmonella Between Animals, Humans, and the Environment

ARS Office/Lab and Location : A research opportunity is currently available with the U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS) at the United States Poultry Research Center located in Athens, Georgia. 

Research Project : The postdoctoral fellow will participate in developing a machine learning model to identify genetic factors that enable particular serotypes and strains of Salmonella to be transmitted from the environment to animals, between animals, and to humans. The fellow will take a “One Health” approach to this issue that includes influence of transmission on antimicrobial resistance (AMR), food safety, animal health, and environmental pollution. This research will utilize Mississippi State University Atlas High Performance Computing Cluster resources. WGS data will be acquired from the Food Safety and Inspection Service (FSIS) isolates from Hazard Analysis and Critical Control Point (HACCP) samples. A genome wide association study (GWAS) approach will be used to identify genetic markers for transmission which will be further characterized and targeted for interventions. The role of the environment in transmission of Salmonella from animals to humans will also be investigated.

A previous comparison of Salmonella isolated from the Upper Oconee Watershed to Salmonella isolated from humans using Pulsed-Field Gel Electrophoresis showed that 46.1% of 1,190 Salmonella isolated from surface water matched isolates from human infections. These matches will be analyzed at a much higher resolution by the fellow comparing WGS data from Salmonella watershed isolates to WGS data from the human isolates. Additionally, our geographic information system (GIS) database includes the location of the 105 sampling sites as well as all sewers, wastewater treatment, and septic systems in the watershed. The fellow will expand the GIS database by adding recreation water access sites, agricultural land use, meat processing plants, poultry houses, and cow-calf farms. Analysis will determine the likelihood of sources as well as the effect of location and proximity to sources on the genetics of the Salmonella. Machine learning and artificial intelligence will be used to find associations and to develop methods to predict Salmonella spread and AMR phenotypes.

Learning Objectives : This project provides the postdoctoral fellow a unique opportunity to use their bioinformatic, computational biology, and GIS skills to help answer questions about how humans, animals, and the environment interact to affect the development of AMR and its transmission between humans, animals, and the environment.

Mentor : The mentor(s) for this opportunity are Drs. Jonathan Frye (jonathan.frye@usda.gov) and Charlene Jackson (Charlene.Jackson@ars.usda.gov). If you have questions about the nature of the research, please contact the mentor.

Anticipated Appointment Start Date : As soon as a qualified candidate is identified.  Start date is flexible and will depend on a variety of factors.

Appointment Length : The appointment will initially be for two years, but may be renewed upon recommendation of ARS and is contingent on the availability of funds.

Level of Participation : The appointment is full-time.

Participant Stipend : The participant will receive a monthly stipend commensurate with educational level and experience. The current stipend for this opportunity will be $5,823.17 plus $562.68 for medical, prescriptions, dental and vision each month.

USDA-ARS-2022-0362  USDA-ARS Postdoctoral Fellowship to Investigate Detection Methods and Vaccines for Persistent Salmonella Infantis Strains and the pESI MDR/Virulence Plasmid

ARS Office/Lab and Location : A research opportunity is currently available with the U.S. Department of Agriculture (USDA), Agricultural Research Service (ARS), within the Bacterial Epidemiology and Antimicrobial Resistance Research Unit located in Athens, Georgia.

The Bacterial Epidemiology and Antimicrobial Resistance Research Unit's mission is to determine causes of antimicrobial resistance (AMR), to understand how Salmonella strains become established in poultry production, and to develop interventions to reduce their impact on human health. The laboratory consists of four PIs, support scientists, technicians, graduate students, undergraduate students, and postdoctoral trainees working in a dynamic team setting. The PIs have diverse interests focused on poultry production and each PI has independent and team projects all striving to improve food safety.

Research Project : Multi-drug resistant (MDR) Salmonella Infantis has been established in U.S. poultry production and is causing a continuing outbreak in humans.  Vaccines to eliminate this dangerous pathogen in U.S. poultry are needed. The postdoctoral fellow will participate in the development of recombinantly expressed subunit vaccines and mRNA vaccines.  These methods allow targeting of specific structures on the cell surface of Salmonella Infantis with neutralizing antibodies, and also benefit from containing no live Salmonella that can be detected in downstream food safety compliance testing. The fellow will also assist in developing assays to detect Salmonella Infantis and the pESI MDR/virulence plasmid it carries for use in determining the epidemiology of this persistent problem in poultry production. Additional research opportunities include environmental monitoring of AMR bacteria in surface water and training in computational biology.  

Learning Objectives : This project provides training in cutting edge recombinant and mRNA vaccine technology, assay development, and exposure to national and regional AMR monitoring programs. 

Mentor : The mentor(s) for this opportunity are Drs. Hung-Yueh Yeh and Jonathan Frye (jonathan.frye@usda.gov). Dr. Yeh will focus on vaccine development and testing and Dr. Frye will focus on assay development and technology transfer. If you have questions about the nature of the research, please contact the mentor.

Anticipated Appointment Start Date : As soon as a qualified candidate is identified.  Start date is flexible and will depend on a variety of factors.

Appointment Length : The appointment will initially be for one year, but may be renewed up to two more years upon recommendation of ARS and is contingent on the availability of funds.

Level of Participation : The appointment is full-time.

Participant Stipend : The participant will receive a monthly stipend commensurate with educational level and experience. The current stipend for this opportunity will be $5,823.17 plus $562.68 for medical, prescriptions, dental and vision each month.